Electronic transitions in quantum dots and rings induced by inhomogeneous off-centered light beams

TL;DR

This paper provides a theoretical analysis of how inhomogeneous and plane-wave light beams, when offset from nanostructures, induce electronic transitions involving orbital angular momentum transfer, revealing control mechanisms based on beam positioning.

Contribution

It introduces exact analytical methods to study off-centered light beams' effects on nanostructures, highlighting the role of beam displacement in controlling electronic transitions.

Findings

Off-centered light beams can induce transitions with different angular momenta.

Transitions are controllable by adjusting the separation between beam and nanostructure.

Even plane-wave beams can cause angular momentum-changing electronic transitions.

Abstract

We theoretically investigate the effect of inhomogeneous light beams with (twisted light) and without (plane-wave light) orbital angular momentum on semiconductor-based nanostructures, when the symmetry axes of the beam and the nanostructure are displaced parallel to each other. Exact analytical results are obtained by expanding the off-centered light field in terms of the appropriate light modes centered around the nanostructure. We demonstrate how electronic transitions involving the transfer of different amounts of orbital angular momentum are switched on and off as a function of the separation between the axes of the beam and the system. In particular, we show that even off-centered plane-wave beams induce transitions such that the angular momenta of the initial and final states are different.